STERIC AND INDUCTIVE EFFECTS IN BINARY-MIXTURES OF ALKANONES WITH BENZENE OR TETRACHLOROMETHANE - COMPARISON WITH DISQUAC PREDICTIONS

Literature data on molar excess enthalpies (H-E), molar excess Gibbs e nergies (G(E)) and activity coefficients at infinite dilution (gamma(i )(infinity)) of linear alkanones + benzene or tetrachloromethane are t reated in the framework of DISQUAC, an extended group contribution mod el. The systems are characterized by three types of contact surfaces: carbonyl (CO group), alkane (CH3 or CH2 groups) and solvent (benzene, C6H6, or tetrachloromethane, CCl4, groups). The interchange energies p arameters of the alkane/CO and alkane/sorvent contacts were determined previously, the interaction parameters of the CO/solvent contacts are reported in this work. The quasi-chemical and dispersive parameters d epend on the environment of the CO group. The model provides a fairly consistent description of the experimental data as a function of conce ntration. The solutions of alkanones in benzene or tetrachloromethane exhibit the features of polar solute + polarizable solvent mixtures, n amely, the deviations from ideality are much less positive than in alk anes and may even be negative. (C) 1998 Elsevier Science B.V.